JP2018025625A - Zoom lens and imaging apparatus having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens having a wide angle, a high magnification, a bright F-number and good optical performance while suppressing the size of the whole optical system, and an imaging apparatus having the zoom lens.SOLUTION: The zoom lens includes, successively disposed from an object side to an image side: a first lens group having a positive refractive power; a second lens group having a negative refractive power; a third lens group having a positive or negative refractive power; and a rear group including one or more lens groups. Upon varying magnifications, the first lens group does not move but an interval between adjoining lens groups varies upon varying magnifications. The first lens group includes three or more lenses, and the second lens group includes three or more lenses. A moving amount of the second lens group upon varying magnifications from a wide angle end to a telephoto end, and a moving amount of the third lens group upon varying magnifications from the wide angle end to the telephoto end are appropriately set.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a zoom lens and an image pickup apparatus having the same, and is suitable for a photographing system such as a digital camera, a video camera, and a TV camera.

  In recent years, higher definition of monitors has progressed, and high quality images are also required for zoom lenses mounted on digital cameras, video cameras, and TV cameras. At that time, the solid-state imaging device is desired to be enlarged in order not to reduce the sensitivity even if the number of pixels is increased, but in order to suppress the enlargement of the entire camera, the zoom lens is required to be further reduced in size. Yes.

  Conventionally, as a zoom lens that is small and can efficiently secure a zoom ratio, it has a lens group having positive and negative refractive power in order from the object side to the image side, and is arranged on the image side from the third lens group. A zoom lens that corrects image plane movement accompanying zooming in a lens group is known.

  For example, Patent Document 1 discloses a zoom lens in which a lens group having positive, negative, positive, and positive refractive power is arranged in order from the object side, and the first lens group is fixed at the time of zooming and is about 10 to 14 times. Yes. In Patent Document 2, a lens group having positive, negative, positive, negative, and positive refractive power is arranged in order from the object side, and a zoom lens of about 10 times is fixed with the first lens group and the fifth lens group fixed during zooming. It is disclosed.

JP 2012-88603 A JP 2012-242617 A

  In Patent Document 1, the second lens group and the third lens group are moved, but the amount of movement of the third lens group is small, and there is a problem in suppressing fluctuations in various aberrations during zooming.

  In Patent Document 2, the F value at the telephoto end is as dark as about F7, and it is difficult to correct spherical aberration and coma at the telephoto end when the magnification is further increased and the aperture is increased.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a zoom lens having a wide-angle high magnification, a small open F value (bright), and good optical performance while suppressing the size of the entire optical system, and an image pickup apparatus having the same. Yes.

In order to achieve the above object, a zoom lens according to the present invention includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a positive or negative lens arranged in order from the object side to the image side. A zoom lens that includes a third lens group having a refractive power and a rear group including one or more lens groups, in which the first lens group does not move during zooming, and an interval between adjacent lens groups changes during zooming. The first lens group includes three or more lenses, the second lens group includes three or more lenses, and the amount of movement of the second lens group during zooming from the wide-angle end to the telephoto end is determined. m2, the amount of movement of the third lens group at zooming from the wide-angle end to the telephoto end is m3, and the sign of the amount of movement when the lens group is located on the image side at the telephoto end is positive compared to the wide-angle end and when,
0.38 <| m3 / m2 |
The following conditional expression is satisfied.

  According to the present invention, it is possible to provide a zoom lens having a wide angle and high magnification, a small open F value (bright), and good optical performance while suppressing the size of the entire optical system, and an imaging apparatus having the zoom lens.

2 is a lens cross-sectional view of an optical system according to Numerical Example 1. FIG. FIG. 5 is an aberration diagram at the wide-angle end in Numerical Example 1. FIG. 4 is an aberration diagram at the intermediate focal length in the numerical value example 1. FIG. 4 is an aberration diagram at the telephoto end of Numerical Example 1. 6 is a lens cross-sectional view of an optical system according to Numerical Example 2. FIG. FIG. 6 is an aberration diagram at the wide-angle end in Numerical Example 2. FIG. 6 is an aberration diagram for the intermediate focal length of Numerical Example 2. FIG. 6 is an aberration diagram at the telephoto end of Numerical Example 2. 10 is a lens cross-sectional view of an optical system according to Numerical Example 3. FIG. FIG. 10 is an aberration diagram at the wide-angle end in Numerical Example 3. FIG. 10 is an aberration diagram for the intermediate focal length of Numerical Example 3. 10 is an aberration diagram at the telephoto end of Numerical Example 3. FIG. 10 is a lens cross-sectional view of an optical system according to Numerical Example 4. FIG. FIG. 10 is an aberration diagram at the wide-angle end in Numerical Example 4. FIG. 10 is an aberration diagram at an intermediate focal length in Numerical Example 4. FIG. 10 is an aberration diagram at the telephoto end of Numerical Example 4. It is a figure for demonstrating embodiment of the imaging device of this invention.

Hereinafter, a zoom lens of the present invention will be described in detail with reference to the accompanying drawings.
The zoom lens of the present invention includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive or negative refractive power, which are arranged in order from the object side to the image side. It is composed of a rear group including one or more lens groups, and is suitable for high magnification zoom. In addition, the first lens unit does not move during zooming, the distance between adjacent lens units changes during zooming, and the zoom lens has a zooming action after the third lens unit, or the image plane varies during zooming. Is corrected.

  The first lens group is composed of three or more lenses, and mainly corrects spherical aberration and axial chromatic aberration on the telephoto side. The second lens group is composed of three or more lenses, and suppresses variations in field curvature and lateral chromatic aberration during zooming. The second lens group has two or more aspheric surfaces on the second and subsequent lenses from the object side. That is, of the lens surfaces of each lens excluding the lens arranged closest to the object among the lenses included in the second lens group, two or more lens surfaces are aspherical. With this configuration, fluctuations in coma from the intermediate focal length to the telephoto end are corrected.

Furthermore, the following conditional expressions are satisfied.
0.38 <| m2 / m3 | (1)
9.00 <ft / fw (2)
Here, ft is the focal length at the telephoto end, fw is the focal length at the wide-angle end, m2 is the amount of movement of the second lens unit in zooming from the wide-angle end to the telephoto end, and m3 is in zooming from the wide-angle end to the telephoto end. The amount of movement of the third lens group, and m2 and m3 are positive signs when the lens group is located on the image side at the telephoto end compared to the wide-angle end.

  Conditional expression (1) is an expression in which the ratio of the amount of movement from the wide-angle end to the telephoto end of the second lens group and the third lens group is defined by an absolute value. When the conditional expression (1) is not satisfied, the amount of movement of the second lens unit is small, and the refractive power of the second lens unit becomes strong in order to secure a desired zoom ratio, and the field curvature during zooming is increased. Correction and spherical aberration correction at the telephoto end becomes difficult.

  Conditional expression (2) defines the zoom ratio. When the conditional expression (2) is not satisfied, the number of means necessary for obtaining the same effect as that of the present invention increases, which is not preferable as a range to which the present invention is applied.

Although the object of the present invention is achieved as described above, it is desirable that the present invention satisfies the following conditional expression.
0.40 <| m3 / f3 | <0.65 (3)
Here, f3 is the focal length of the third lens group.

  Conditional expression (3) is an expression in which the ratio of the amount of movement from the wide-angle end to the telephoto end of the third lens group and the focal length of the third lens group is defined as an absolute value. When the upper limit condition of the conditional expression (3) is not satisfied, it is necessary to largely move the third lens unit having a strong refractive power, so that it is difficult to suppress the curvature of field and the fluctuation of coma during zooming. On the contrary, when the lower limit condition of the conditional expression (3) is not satisfied, the contribution of the third lens group to zooming becomes small, and it is difficult to achieve a high zooming ratio.

In the present invention, it is preferable that the following conditional expression is satisfied.
0.1 <m2 / ft <0.3 (4)

  Conditional expression (4) defines the amount of movement of the second lens group from the wide-angle end to the telephoto end and the focal length of the telephoto end. When the upper limit condition of the conditional expression (4) is not satisfied, the total lens length becomes long, which is not preferable. On the contrary, when the lower limit condition of the conditional expression (4) is not satisfied, the refractive power of the second lens group necessary for securing the desired zoom ratio becomes strong, and the variation in curvature of field during zooming, It becomes difficult to correct spherical aberration at the telephoto end.

In the present invention, it is preferable that the following conditional expression is satisfied.
1.3 <m2 / D1 <3.0 (5)
However, D1 is the thickness on the optical axis of the first lens group.

  Conditional expression (5) defines the ratio of the amount of movement of the second lens group from the wide-angle end to the telephoto end and the thickness of the first lens group on the optical axis. When the upper limit condition of the conditional expression (5) is not satisfied, the moving distance of the second lens group is large, so that the entrance pupil at the intermediate focal length becomes long, leading to an increase in the front lens diameter, which is not preferable. On the contrary, when the lower limit condition of the conditional expression (5) is not satisfied, the refractive power of the second lens group necessary for securing the desired zoom ratio becomes strong, and the variation of the field curvature during zooming, It becomes difficult to correct spherical aberration at the telephoto end. Alternatively, by increasing the number of constituent elements of the first lens group, it is possible to correct the spherical aberration and coma aberration at the telephoto end as in the effect of the present invention, and do not conform to the spirit of the invention.

In the present invention, it is desirable that the third lens group includes at least one negative lens.
When the third lens group is a lens group having negative refractive power, it is obvious that the third lens group includes at least one negative lens. In the case where the third lens group is a lens group having a positive refractive power, it is preferable to include at least one negative lens in order to suppress fluctuations in axial chromatic aberration during zooming.

In the present invention, it is desirable that the zoom lens has an aperture stop closer to the image side than the lens arranged fourth from the lens arranged adjacent to the image side of the first lens group.
It is desirable that the lens disposed on the object side with respect to the stop has at least four lenses in addition to the first lens group in order to suppress variations in field curvature and lateral chromatic aberration during zooming.

It is more desirable to specify the numerical ranges of conditional expressions (1) to (5) as follows.
0.38 <| m3 / m2 | <1.00 (1a)
9.40 <ft / fw <30.00 (2a)
0.43 <| m3 / f3 | <0.62 (3a)
0.16 <m2 / ft <0.28 (4a)
1.4 <m2 / D1 <2.7 (5a)

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
1, 5, 9, and 13 are lens cross-sectional views of Numerical Examples 1 to 4 described later, and FIGS. 2 to 4, 6 to 8, 10 to 12, and 14 to 16 are aberration diagrams of the Numerical Examples, respectively. is there. 2 to 4, 6 to 8, 10 to 12, and 14 to 16, FIGS. 2, 6, 10, and 14 are aberration diagrams at the wide angle end, and FIGS. 3, 7, 11, and 15 are aberration diagrams at the intermediate focal length. 4, 8, 12, and 16 are aberration diagrams at the telephoto end. In the aberration diagrams, d and g are d and g lines, M and S are meridional image surfaces and sagittal image surfaces, and lateral chromatic aberration is represented by g lines.

  In the lens cross-sectional views of FIGS. 1, 5, 9, and 13, L1 to L5 are first to fifth lens groups, SP is a stop, P is a glass block such as a CCD face plate and low-pass filter, and I is an image plane. . In the present embodiment, when zooming from the wide-angle end to the telephoto end, each group is moved as indicated by arrows in FIGS. A solid line and a dotted line arrow are movement trajectories for correcting image plane fluctuations accompanying zooming when focusing on an object at infinity and an object at close distance, respectively.

なる式で表している。また、例えば「e−Z」の表示は「×10^−Z」を意味する。
半画角は光線追跡で求めた値である。ＢＦはバックフォーカスである。
Numerical examples of the present invention will be described below.
In numerical examples, Ri is the radius of curvature of the i-th surface in order from the object side to the image side, Di is the distance between the i-th surface and the i + 1-th surface (lens thickness or air space), Ni and νi. Are the refractive index and Abbe number of the material of the i-th lens, respectively. Note that the Abbe number ν is Nd, NF, and NC when the refractive indexes for the d-line (587.6 nm), F-line (486.1 nm), and C-line (656.3 nm) of the Fraunhofer line are Nd, NF, and NC, respectively.
v = (Nd-1) / (NF-NC)
It is represented by The aspherical shape has an X axis in the optical axis direction, a h-axis direction perpendicular to the optical axis, a positive light traveling direction, R is a paraxial radius of curvature, and each aspheric coefficient is k, A3, A4, A5, A6, When A7, A8, A9, A10, A11,

It is expressed by the following formula. For example, “e-Z” means “× 10 ^−Z ”.
The half angle of view is a value obtained by ray tracing. BF is a back focus.

(Numerical example 1)
Unit mm

Surface data surface number i ri di ndi νdi
1 205.771 2.43 1.88202 37.2
2 76.326 8.50 1.49700 81.5
3 -554.860 0.17
4 83.963 4.95 1.49700 81.5
5 471.683 0.17
6 60.944 6.40 1.49700 81.5
7 338.896 (variable)
8 779.821 1.29 1.81600 46.6
9 20.025 6.00
10 -409.205 1.01 1.75520 27.5
11 51.248 4.19
12 * -44.288 1.38 1.76182 26.5
13 * 303.515 2.19
14 * 80.056 3.72 1.95906 17.5
15 * -81.660 (variable)
16 (Aperture) ∞ (Variable)
17 * 22.030 2.71 1.71300 53.9
18 89.912 12.28
19 995.895 0.68 1.80 100 35.0
20 19.475 2.23
21 * 30.346 3.80 1.43875 94.9
22 -44.887 (variable)
23 36.031 6.83 1.55332 71.7
24 -31.566 0.95 1.80000 29.8
25 -60.832 (variable)
26 ∞ 5.41 1.51633 64.1
27 ∞ 1.00
Image plane ∞

Aspheric data 12th surface
K = 5.23415e + 000 A 4 = -3.11189e-007 A 6 = 1.59319e-009 A 8 = 2.96297e-011

Side 13
K = 2.18962e + 002 A 4 = -8.66971e-006 A 6 = -3.38267e-008 A 8 = 1.92247e-011

14th page
K = 1.62820e + 001 A 4 = -1.32117e-006 A 6 = -9.87946e-009 A 8 = -2.47899e-012

15th page
K = -1.70303e + 000 A 4 = 1.62089e-006 A 6 = 1.49766e-008 A 8 = -5.46582e-012

17th page
K = -2.51602e-001 A 4 = -2.46794e-006 A 6 = 8.49427e-010 A 8 = -5.03456e-012

21st page
K = 1.49921e-001 A 4 = 3.83415e-007 A 6 = 1.35245e-008 A 8 = 8.58053e-011

Various data Zoom ratio 19.50
Wide angle Medium telephoto focal length 10.60
F number 3.61 3.61 3.61
Half angle of view 36.10 5.85 2.03
Image height 7.41 7.41 7.41
Total lens length 198.01 198.01 198.01
BF 30.92 37.81 16.95

d 7 1.07 44.12 54.88
d15 58.30 15.25 4.48
d16 33.67 9.17 1.40
d22 2.17 19.78 48.41
d25 26.35 33.24 12.38

Zoom lens group data group Start surface Focal length
1 1 85.73
2 8 -21.38
3 17 69.13
4 23 49.32

(Numerical example 2)
Unit mm

Surface data surface number i ri di ndi νdi
1 178.057 1.96 1.83400 37.2
2 60.001 7.86 1.43875 94.9
3 -272.136 0.17
4 57.855 5.83 1.49700 81.5
5 -3611.688 0.17
6 57.398 3.43 1.53775 74.7
7 141.092 (variable)
8 -2080.933 0.81 1.88300 40.8
9 13.493 5.50
10 * -23.944 0.67 1.78800 47.4
11 * 57.657 0.17
12 43.172 2.83 1.92286 18.9
13 -45.354 (variable)
14 -28.939 0.60 1.78800 47.4
15 -56.254 (variable)
16 (Aperture) ∞ (Variable)
17 * 13.007 3.00 1.58313 59.4
18 * -257.031 2.89
19 35.108 0.60 1.91082 35.3
20 12.563 0.46
21 16.699 2.44 1.49700 81.5
22 -62.916 0.17
23 19.387 0.60 1.88300 40.8
24 13.631 2.78 1.43875 94.9
25 -45.218 (variable)
26 158.534 1.33 2.00069 25.5
27 -20.449 0.60 1.88300 40.8
28 13.888 (variable)
29 -49.729 2.35 1.53775 74.7
30 -12.812 0.60 1.95375 32.3
31 -42.155 0.58
32 43.037 2.61 1.63980 34.5
33 -29.595 (variable)
34 ∞ 2.00 1.51633 64.1
35 ∞ 1.00
Image plane ∞

Aspheric data 10th surface
K = -1.12535e + 000 A 4 = -2.56278e-005 A 6 = 5.48500e-008 A 8 = -4.27510e-010

11th page
K = -6.36388e + 000 A 4 = -2.46799e-005 A 6 = 1.11088e-007 A 8 = -2.45457e-010

17th page
K = -2.48049e-001 A 4 = -1.31894e-005 A 6 = 2.64986e-009 A 8 = 8.62890e-010

18th page
K = -8.54422e + 002 A 4 = 2.95116e-005 A 6 = 1.13204e-008 A 8 = 4.58515e-010

Various data Zoom ratio 19.50
Wide angle Medium Telephoto focal length 11.39 61.47 222.04
F number 4.12 4.63 4.84
Half angle of view 35.60 6.65 1.86
Image height 7.41 7.41 7.41
Total lens length 139.25 139.25 139.25
BF 14.35 14.07 13.37

d 7 1.25 35.33 49.94
d13 6.09 5.37 1.23
d15 45.09 11.72 1.26
d16 1.24 1.24 1.24
d25 2.06 9.89 4.41
d28 18.16 10.61 16.79
d33 12.03 11.75 11.06

Zoom lens group data group Start surface Focal length
1 1 71.09
2 8 -14.83
3 14 -76.37
4 17 18.09
5 26 -19.60
6 29 56.59

(Numerical Example 3)
Unit mm

Surface data surface number i ri di ndi νdi
1 190.498 2.01 1.83400 37.2
2 48.074 9.76 1.49700 81.5
3 -275.908 0.17
4 49.204 6.30 1.53775 74.7
5 929.826 0.17
6 43.680 4.40 1.55332 71.7
7 127.333 (variable)
8 232.205 0.82 2.00 100 29.1
9 12.212 5.97
10 * -23.519 0.67 1.75501 51.2
11 * 43.830 0.60
12 37.196 3.52 1.94595 18.0
13 -32.398 (variable)
14 -20.077 0.60 1.77250 49.6
15 -278.037 (variable)
16 (Aperture) ∞ (Variable)
17 * 12.667 3.45 1.58313 59.4
18 * -366.921 0.81
19 18.136 0.83 1.95375 32.3
20 11.536 0.43
21 13.559 3.81 1.43875 94.9
22 -34.811 0.17
23 35.420 0.63 1.88300 40.8
24 9.937 3.61 1.51742 52.4
25 -97.438 (variable)
26 45.205 1.20 1.92286 18.9
27 -51.299 0.60 1.95375 32.3
28 15.586 (variable)
29 179.006 2.98 1.51742 52.4
30 -11.229 0.60 1.85 150 40.8
31 77.139 0.17
32 30.328 3.29 1.53172 48.8
33 -17.932 (variable)
34 ∞ 2.00 1.51633 64.1
35 ∞ 1.00
Image plane ∞

Aspheric data 10th surface
K = -1.42680e + 000 A 4 = -3.03718e-005 A 6 = 1.69961e-008 A 8 = -3.62871e-010

11th page
K = 4.43821e + 000 A 4 = -4.70125e-005 A 6 = 1.11725e-007 A 8 = -2.43024e-010

17th page
K = -6.79097e-001 A 4 = 7.72525e-006 A 6 = 6.08844e-008 A 8 = 4.12175e-010

18th page
K = -7.48650e + 002 A 4 = 4.91668e-005 A 6 = -5.77852e-008 A 8 = -1.55308e-011

Various data Zoom ratio 19.50
Wide angle Medium Telephoto focal length 10.78 53.60 210.20
F number 4.12 4.63 4.84
Half angle of view 35.6 7.62 1.96
Image height 7.41 7.41 7.41
Total lens length 139.33 139.33 139.33
BF 12.91 12.91 12.91

d 7 0.93 25.46 35.97
d13 9.31 9.29 8.57
d15 36.57 12.07 2.27
d16 1.20 1.20 1.20
d25 1.39 15.45 13.21
d28 19.47 5.41 7.65
d33 10.59 10.59 10.59

Zoom lens group data group Start surface Focal length
1 1 55.38
2 8 -17.45
3 14 -28.04
4 17 18.06
5 26 -24.86
6 29 89.78

(Numerical example 4)
Unit mm

Surface data surface number i ri di ndi νdi
1 127.848 1.60 1.91650 31.6
2 44.188 6.28 1.43875 94.9
3 -398.741 0.17
4 54.825 3.29 1.43875 94.9
5 225.850 0.17
6 46.091 3.91 1.76385 48.5
7 339.544 (variable)
8 -440.844 0.82 1.83481 42.7
9 11.543 4.17
10 * 1425.898 0.62 1.58313 59.5
11 * 41.873 3.41
12 -14.168 0.62 1.43700 95.1
13 -165.224 0.17
14 104.120 1.82 1.92286 18.9
15 -56.837 (variable)
16 (Aperture) ∞ (Variable)
17 * 16.025 4.18 1.58313 59.4
18 * -93.303 3.01
19 91.910 0.61 1.83400 37.2
20 17.277 1.16
21 35.972 2.60 1.43700 95.1
22 -42.626 0.50
23 20.001 0.60 1.95375 32.3
24 13.670 3.94 1.53775 74.7
25 -69.764 (variable)
26 -56.658 1.19 2.00069 25.5
27 -22.673 0.83 1.69680 55.5
28 21.417 (variable)
29 179.722 4.21 1.49700 81.5
30 -18.637 0.76 2.00069 25.5
31 -36.055 0.17
32 28.209 4.39 1.53775 74.7
33 -51.301 (variable)
34 ∞ 2.00 1.51633 64.1
35 ∞ 1.00
Image plane ∞

Aspheric data 10th surface
K = 2.54189e + 004 A 4 = 8.39651e-005 A 6 = -2.31743e-006 A 8 = 1.32338e-008

11th page
K = 1.08019e + 001 A 4 = 2.59711e-005 A 6 = -2.56179e-006 A 8 = 1.40038e-008

17th page
K = -2.67657e-001 A 4 = -1.11197e-005 A 6 = -1.56889e-008 A 8 = -4.86597e-011

18th page
K = -5.34856e + 001 A 4 = 7.30667e-006 A 6 = -9.86003e-009 A 8 = 1.16698e-012

Various data Zoom ratio 14.55
Wide angle Medium Telephoto focal length 8.76 51.43 127.38
F number 2.88 3.74 4.63
Half angle of view 40.4 8.02 3.26
Image height 6.45 7.41 7.41
Total lens length 139.21 139.21 139.21
BF 14.02 14.02 14.02

d 7 1.00 24.38 34.39
d15 35.19 11.82 1.80
d16 13.55 0.70 0.70
d25 2.34 15.01 14.68
d28 17.91 18.09 18.42
d33 11.70 11.70 11.70

Zoom lens group data group Start surface Focal length
1 1 55.39
2 8 -10.72
3 17 21.92
4 26 -26.98
5 29 30.65

Table 1 shows the relationship between the above-described conditional expressions and various numerical values in the numerical examples.

  As described above, according to each embodiment, it is possible to realize a zoom lens having a small F value (brighter) and good optical performance while suppressing the size of the entire optical system.

  Next, an embodiment of a video camera using the zoom lens of the present invention as a photographing optical system will be described with reference to FIG.

  In FIG. 17, 10 is a video camera body, 11 is a photographing optical system constituted by the zoom lens of the present invention, 12 is an image pickup device such as a CCD that receives a subject image by the photographing optical system 11, and 13 is light receiving by the image pickup device 12. A recording means 14 for recording the subject image, and a finder for observing the subject image displayed on a display element (not shown). The display element is constituted by a liquid crystal panel or the like, and a subject image formed on the image sensor 12 is displayed.

  In this way, by applying the imaging apparatus of the present invention to an optical apparatus such as a video camera, an optical apparatus having a small size and high optical performance can be realized.

  If an electronic image sensor such as a CCD is used as the image sensor, the output image can be further improved in image quality by electronically correcting aberrations.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

L1 1st lens group L2 2nd lens group L3 3rd lens group L4 4th lens group L5 5th lens group L6 6th lens group

Claims (9)

A first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive or negative refractive power, and one or more lens groups arranged in order from the object side to the image side. A zoom lens configured to include a rear group, wherein the first lens group does not move during zooming, and an interval between adjacent lens groups changes during zooming,
The first lens group includes three or more lenses, and the second lens group includes three or more lenses,
The amount of movement of the second lens group at zooming from the wide-angle end to the telephoto end is m2, and the amount of movement of the third lens group at zooming from the wide-angle end to the telephoto end is m3. When the sign of the amount of movement when the lens group is located on the image side at the end is positive,
0.38 <| m3 / m2 |
A zoom lens satisfying the following conditional expression: When the focal length of the zoom lens at the wide angle end is fw and the focal length of the zoom lens at the telephoto end is ft,
9.00 <ft / fw
The zoom lens according to claim 1, wherein the following conditional expression is satisfied. When the focal length of the third lens group is f3,
0.40 <| m3 / f3 | <0.65
The zoom lens according to claim 1, wherein the following conditional expression is satisfied. When the focal length of the zoom lens at the telephoto end is ft,
0.1 <m2 / ft <0.3
The zoom lens according to claim 1, wherein the following conditional expression is satisfied. When the thickness on the optical axis of the first lens group is D1,
1.3 <m2 / D1 <3.0
The zoom lens according to claim 1, wherein the following conditional expression is satisfied.   The zoom lens according to any one of claims 1 to 5, wherein the third lens group includes a negative lens.   7. The aperture stop on the image side of the lens arranged fourth from the lens arranged adjacent to the image side of the first lens group, according to claim 1. The described zoom lens.   2. The lens surfaces of each lens excluding the lens arranged closest to the object among the lenses included in the second lens group, wherein two or more lens surfaces are aspherical. The zoom lens according to any one of 1 to 7.   An image pickup apparatus comprising: the zoom lens according to claim 1; and an image pickup element that receives an image formed by the zoom lens.

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